@book{RM-6037-PR,
author="Casti, J. L. and Robert E. Kalaba",
title="Proof of the Basic Invariant Imbedding Method for Fredholm Integral Equations with Displacement Kernels — I",
address="Santa Monica, CA",
year="1969",
doi="10.7249/RM6037",
publisher="RAND Corporation"
}